This invention relates to inflatable structures and particularly to such structures comprising rubberized fabric sheet material.
Many inflatable structures in use today are composed of rubberized fabric sheet material. The kind of fabric sheet utilized in these structures often depends on the particular use or service conditions associated with the inflatable.
Several such inflatables find particular use in emergency situations where the inflatable is packed or stowed in uninflated condition and inflated for utilization upon the occurrence of an emergency. Examples of such emergency devices are aircraft evacuation slides or slide raft combinations, life rafts, off-shore oil drilling platform evacuation slides and helicopter flotation tubes. In these inflatable emergency devices, it is important that the particular fabric sheet which constitutes principally the body of the inflatable be relatively lightweight yet of adequate strength. Thus, the strength to weight ratio of a fabric selected for use in emergency inflatables is of importance.
Also, characteristics in these inflatables is the fact that certain portions of the device can be more susceptible to tear, abrasion, etc., than are other portions. For example, in aircraft or off-shore evacuation slides, the sliding surface of the device is subject to stresses, abrasion and other distinctive forces which could tear or otherwise adversely affect that surface to the point where the device would be inoperable. The specific disposition of the sheet material thus often suggests use of a material of high tear resistance in addition to one of high strength to weight ratio.